1. Field of the Invention
The present invention relates to ladders. More particularly, it relates to leveling ladders for use on uneven surfaces.
2. The Prior Art
The patent to Griffith, U.S. Pat. No. 5,232,067, discloses a stile extending attachment for a ladder. The invention consists of an attachment device for use on a ladder having hollow rungs and two side stile members. A long bolt is inserted through two of the hollow rungs and extending from one side stile through to the other and through the attachment device. The attachment device is releasably fastened by a nut and washer at each of the through bolts, thereby allowing the adjustment of the length of one of the two side stile members of the ladder.
The patent to Thocher et al., U.S. Pat. No. 5,273,133, discloses a ladder leveler. The invention consists of a mechanical gear system and extension member. Upon manually rotating the gear mechanism, the side member will extend or retract according to the direction of the rotation. A means for locking the gear system in place is provided.
U.S. Pat. No. 5,107,958 to Johnson, discloses a ladder leveler. The invention consists of a pair of leg extensions that are releasably affixed to the end of the side rails of the ladder. The extensions have a tightening bolt and a tension spring to secure the extension at a desired height. The extensions shown, fit over the end of the side rails and can be affixed thereto with screws or the like.